Engadget: Here’s an interesting tidbit. Denon’s admittedly pricey AVR-4311CI — which was introduced in late April — may very well end up being the first major product to gain iTunes AirPlay compatibility retroactively. Yeah, retroactively. According to an updated product listing, the AVR will see a “planned upgrade” in the fall of 2010 that will “provide Apple iTunes AirPlay compatibility [that will let you] stream your favorite music to the AVR-4311CI.” Now, we already knew that Denon was a partner of both Apple and BridgeCo (the enabling company behind AirPlay), but this is first mention of any existing product receiving a simple upgrade (firmware, we’re guessing) that would add support for Apple’s newly touted streaming feature. In other words, this may mean that hundreds, if not thousands, of AirPlay compatible devices are already on the market, and just as soon as Apple and / or BridgeCo green-lights the respective firmware updates, home entertainment systems everywhere may gain support for a protocol that wasn’t even public before last week. Here’s hoping, right?